TrailManor Owner's Forum - View Single Post - Dim Front Half Ceiling Lights and No Speakers

**Bill** · 07-03-2013, 08:47 AM

You have two six-volt batteries, with the fuse between them. That is an unusual hookup - do you know how it got there? Is there a second fuse coming off the + terminal of one of the batteries? Other than the fuse, is there any connection to anything from between the two batteries? Can you take a photo of the two batteries and their connection wires? Are your batteries connected exactly as shown in the 6-volt half of this diagram?

http://www.trailmanorowners.com/foru...&pictureid=451

The fact that the 30 amp fuse blew, and the very rugged fuseholder melted, but none of the smaller fuses blew, suggests that there was a short, perhaps momentary, right at the batteries. With the fuse between the two batteries, a momentary connection between the positive posts of the two batteries would blow this fuse in spectacular style. Similarly, a momentary connection between the negative posts of the two batteries would do the same. Did someone try to put the batteries in parallel for a moment, rather than series?

I'm not sure how this would result in a very low voltage on only some of the circuits, as you descirbe. It would depend on the details of the momentary wrong connection. But I tend to agree with other posts that it might have mucked up a ground connection somewhere.

You need to start probing around with a voltmeter. For instance, open up one of the "bad" light fixtures in the front shell. Clip the negative probe of the voltmeter on a known good ground such as the sheet metal of the ceiling skin. Now turn on the light and put the positive (red) probe on one side of the switch, then the other side of the switch, then the center connection to the bulb, and then the shell of the bulb. The first three should all show close to 12 volts. The shell of the bulb should show zero.

By the way, unless something has changed, the front roof and the rear roof are on separate circuits with separate fuses, each 15-amp. So the fact that the rear roof works but the front roof is funny isn't really definitive.

As for the radio, it is on yet a different circuit from the roof circuits. When the TM leaves the factory, the power wires for the radio are left lying on top of the refrig (capped off, of course). The wires are colored, probably white and black or white and blue, though I can't be sure. The speaker wires are also left lying on the top of the refrig, and their insulation is clear. As also stated above, the speakers should never be tied into any of the power wiring, anywhere, any time. If the speakers were connected to the power wiring, this would possibly/probably destroy them more or less instantly.

Interesting set of symptoms. Let us know more as you find more.

Bill

07-03-2013, 08:47 AM	#4
Bill Site Team Join Date: Feb 2003 Location: The mountains of Scottsdale, AZ, and the beaches of Maine Posts: 10,104	You have two six-volt batteries, with the fuse between them. That is an unusual hookup - do you know how it got there? Is there a second fuse coming off the + terminal of one of the batteries? Other than the fuse, is there any connection to anything from between the two batteries? Can you take a photo of the two batteries and their connection wires? Are your batteries connected exactly as shown in the 6-volt half of this diagram? http://www.trailmanorowners.com/foru...&pictureid=451 The fact that the 30 amp fuse blew, and the very rugged fuseholder melted, but none of the smaller fuses blew, suggests that there was a short, perhaps momentary, right at the batteries. With the fuse between the two batteries, a momentary connection between the positive posts of the two batteries would blow this fuse in spectacular style. Similarly, a momentary connection between the negative posts of the two batteries would do the same. Did someone try to put the batteries in parallel for a moment, rather than series? I'm not sure how this would result in a very low voltage on only some of the circuits, as you descirbe. It would depend on the details of the momentary wrong connection. But I tend to agree with other posts that it might have mucked up a ground connection somewhere. You need to start probing around with a voltmeter. For instance, open up one of the "bad" light fixtures in the front shell. Clip the negative probe of the voltmeter on a known good ground such as the sheet metal of the ceiling skin. Now turn on the light and put the positive (red) probe on one side of the switch, then the other side of the switch, then the center connection to the bulb, and then the shell of the bulb. The first three should all show close to 12 volts. The shell of the bulb should show zero. By the way, unless something has changed, the front roof and the rear roof are on separate circuits with separate fuses, each 15-amp. So the fact that the rear roof works but the front roof is funny isn't really definitive. As for the radio, it is on yet a different circuit from the roof circuits. When the TM leaves the factory, the power wires for the radio are left lying on top of the refrig (capped off, of course). The wires are colored, probably white and black or white and blue, though I can't be sure. The speaker wires are also left lying on the top of the refrig, and their insulation is clear. As also stated above, the speakers should never be tied into any of the power wiring, anywhere, any time. If the speakers were connected to the power wiring, this would possibly/probably destroy them more or less instantly. Interesting set of symptoms. Let us know more as you find more. Bill __________________ 2020 2720QS (aka 2720SL) 2014 Ford F-150 4WD 5.0L Bill's Tech Stuff album